Process for preparing a synthetic resin composition



Patented Feb. 16, 1937 UNITED STATES PATENT OFFICE PROCESS FOR PREPARING: SYNTHETIC RESIN COMPOSITION Sydney Leonard Morgan Saunders,

London, England No Drawing. Application March 2, 1935, Serial No. 9,105. In Great Britain December 21, 1933 3 Claims.

nitrocellulose. It has, therefore, been found necessary to modify these resins in order to improve their solubility and compatibility by replacing a portion of the polybasic organic anhydride with a monobasic acid such as for example, that derived from a drying oil.

It has been proposed to react the polybasic organic anhydride with the polyhydric alcohol,

and before the reaction is complete, to'introduce a quantity of fatty acid, such as thatderived from iinseed oil, Now owing to the nature of the acid, it is not miscible with the partially condensed reaction -mixture, and consequently "it separates, and it is only by prolonged heating with vigorous .stir'rifng that complete admixture is obtained.

It hasv now been discovered that the. partially condensed reaction mixture is soluble wlthinwide limits in a partial'esterof a polyhydric alcohol and a monobasic acid;

According to the present invention,.fa processfor preparing a modified alkyd resin comprises the addition of a partially esterified polyhydric alcohol containing, at least two free hydroxyl 'densate or to their admixture.

groupsfthe acid constituent'being a "monobasic acid such asbenzoic, or acetic acids, or the acids derived from vegetable oils, or from naturally occurring. resins, to the product obtained from the incomplete condensation of a polybasi'c or- V ganic anhydride and a polyhydric alcohol and continuing the condensation reaction.

'IEhe inventionv also includes a process .according to the preceding paragraph, erein an excess of the polybasic organic anhy ide sumcient to combine with the partial ester, is, added to the. initial condensation product at any stage, or to the partial ester prior to addition to the con- The invention also includes a process wherein .jcondensatlon is carried out in the presence of vegetable oils which may be heat-treated and/or naturally occurring resins or esteriiied resins. Alternatively the partial ester'may be heat-treated prior to its addition to the condensation product.

The invention further includes lacquers, (for example, those made 'from nitro-cellulose, cellulose acetate) comprising synthetic resin compositions produced by the process described herein.

The following examples illustrate the nature of this invention, but do not restrict it. The parts'are by weight:--

Example 1 20 parts of 'phthalic anhydride and? parts of glycerine are heated together for 30 minutes at- 160-170 Ciand then 15 parts of the mono glycerol ester'of linoleic acid is added, and the mixture h-eated to.25'0-260 C. for 1 hours.

' The product may bev thinned with hydrocarbon,

and the necessary driers added.

Example 2 w I parts of phthalic anhydride and 40 parts of glycerine' are heated together for 20 minutes at I -1'70 (2., and then 148 parts 01' the mono-v glyceride of linoleic acid together with a .further 60 parts of ,phthalic anhydride are added, and the 'fcondensation continued for 2 -hours at 250- 1. ,A process for preparing a synthetic resin composition whichhconsists in heating glycerol and phthalic anhydride together until partial re-- 1 a drying oilacid and continuingthe heating at action occurs, then adding'a mono-glyceride of p a. sufficient temperature sation reaction.

2. A process for preparing a synthetic resin to .completethe, conde'm 'compositionwhich consists in heating glycerol and phthalic anhydride together at 160 C.- C. for 30 minutes, then adding the mono-glycerol- "3. A process for preparing a synthetic resin composition which consists in heating glycerol .andEphthaIic anhydride together at 160, 'C.-

ester of linolelc acid and'further heating the .mlxture at 250 C.- 26 0 C. for 1% hours.

170 c. for 20 minutes, then adding the monoglycerol ester of linoleic {acid together with further phthalic anhydride (and further heating the mixtureat 250 erasu e. for 2, hours.

SYDNEY LEONARD vMORGAN SAUNDERS. 

